Neuropathology 1: CVD Flashcards
name the 3 types of glial cell
astrocytes - most prevalent
oligodendrocytes
ependymal cells
ependymal cells line..
the ventricular system
what is the pathological cellular response seen in stroke?
rapid necrosis with sudden acute functional failure
what kind of neuronal damage occurs as a result of hypoxia?
acute neuronal injury with irreversible shrinking and angulation of nuclei, loss of the nucleolus and a RED cytoplasm
when does acute neuronal injury occur in relation to the time of injury
12-24 hours after injury
name the axonal reaction to injury?
increased protein synthesis
degeneration of myelin sheath and axons distal to injury
what does chronic degeneration of a neuron look like?
shrunken, angulated and lost neurons
small dark nuclei
neuronal tissue replaced by reactive gliosis
small dark nuclei are an example of what damage?
chronic damage
what are inclusions? what are they common in?
subcellular alterations common in neurodegenerative conditions eg alzheimers and in aging
oligodendrocytes are sensitive to ___ damage
oxidative
damage to the myelin sheath poses what risks?
conduction reduced
axons exposed to injury
damage to what cells is a feature of demyelinating disorders
oligodendrocytes
star shaped cells with multipolar cytoplasmic processes describe….
astrocytes
what do the cytoplasmic processes of astrocytes do?
envelop synaptic plates
wrap around vessels and capillaries of the brain
what cells are responsible for reabsorbing and recycling glutamate?
astrocytes
what pathological process is the main indicator of CNS injury?
gliosis
describe gliosis
astrocyte hyperplasia and hypertrophy
prominent nucleolus
small dark nuclei
describe the role of M1 microglia
anti-inflammatory, phagocytic, for acute injury
describe the role of M2 microglia
pro-inflammatory, for chronic injury
which type of microglia is for chronic injury
M2
what happens to microglia when theyre injured?
they proliferate, are recruited via inflammatory mediators and form aggregates around necrotic tissue
most common cause of nervous system injury?
hypoxia
the brain consumes __ % of the body’s total oxygen
20
describe the process of excitotoxicity
energy failure in the cell results in degradation of the mP -> glutamate released but not reabsorbed well -> severe excitation -> Ca excess
excess Ca as a result of excitotoxicity has what consequences?
oxidative stress
apoptisis
mitochondrial dysfunction
protease activation
what happens in cytotoxic oedema? what can it lead to?
excess Na and Cl in the cell cause water to move into the cells across the BBB causing ionic oedema
vasogenic oedema occurs in what brain pathologies?
trauma, tumours, inflammation
encephalopathy
the brain receives __% of the cardiac output
15
global hypoxic ischaemic damage can occur in the context of…
generalised reduction in perfusion/oxygenation
cardiac arrest
severe hypotension
focal hypoxic ischaemic damage can occur in the context of…
vascular obstruction
what parts of the brain are more susceptible to ischaemic damage?
areas between arterial territories
neurons are more sensitive than glial cells to hypoxic ischaemic damage T or F
T, especially purkinje cells in the cerebellum
what kind of infarctive stroke is most common?
thrombotic
most common area for a thrombotic infarctive stroke
middle cerebral artery
where do cardioemboli tend to arise from?
internal carotids
aorta
heart
after 12-24hrs of cerebral infarction what does the brain look like microscopically?
red neurons, oedema
what becomes the predominant cell type -14 days after a cerebral infarction?
microglia
when does gliosis begin after a cerebral infarction
1 week
when does a gliotic scar appear after a cerebral infarction
after a few weeks
clinical presentation of a middle cerebral artery occlusion
weakness in contralateral face and arm
what is arteriolosclerosis
thicker, stiff, weaker arterioles
lacunar infarcts occur from occlusion of….
small penerating arteries
clinical presentation of hypertensive encephalopathy?
severely hypertensive
symptoms of raised ICP
pathological findings of hypertensive encephalopathy?
arteriolar fibrinoid necrosis
petechiae
tentorial and tonsillar herniation
global cerebral oedema
what does amyloid do to BVs
thins their walls making them more likely to rupture
most likely area for an intracerebral haemorrhage
in basal ganglia
most common cause of subarachnoid haemorrhage?
berry aneurysm rupture
most common area of berry aneurysms?
around arterial bifurcations arising from the cirle of willis
in territory of internal carotid
complications of subarachnoid haemorrhage
infarcts in brain parenchyma
intracerebral haematomas
hydrocephalus
